1. Field of the Invention
The present invention relates to a solid-state imaging device, a manufacturing method thereof, and an electronic apparatus, and more particularly, to a solid-state imaging device in which a plurality of photoelectric conversion units are disposed on an imaging surface of a substrate, and a plurality of inner-layer lenses are formed in shapes protruding in directions toward the photoelectric conversion units, a manufacturing method thereof, and an electronic apparatus.
2. Description of the Related Art
Electronic apparatuses such as a digital video camera and a digital camera include solid-state imaging devices. For example, the solid-state imaging device includes a CMOS (Complementary Metal Oxide Semiconductor)-type image sensor and a CCD (Charge Coupled Device)-type image sensor.
In the solid-state imaging devices, an image forming area in which a plurality of pixels are formed is disposed on a surface of a semiconductor substrate. In each of the plurality of pixels, a photoelectric conversion unit that generates signal electric charges by receiving incident light through a curved lens and performing photoelectric conversion for the received light is disposed. For example, a photo diode is formed as the photoelectric conversion unit.
In the solid-state imaging device, for example, an on-chip lens is disposed on the upper side of the photoelectric conversion unit. A configuration in which an inner-layer lens is disposed between the photoelectric conversion unit and the on-chip lens has been proposed. The inner-layer lens is disposed for efficiently irradiating light that is incident through the on-chip lens onto the photoelectric conversion unit. For example, each of a plurality of inner-layer lenses are formed to have a downward convex structure protruding in directions toward the photoelectric conversion unit (for example, see JP-A-2002-359363 and JP-A-2007-324481).